textproduct: Quad Cities

KEY MESSAGES

- Quiet and comfortable weather through Friday.

- Warmer temperatures are expected Sunday onward.

- THe forecast becomes more active this weekend through much of next week with daily chances of showers and storms.

SHORT TERM /THROUGH FRIDAY/

Issued at 1254 AM CDT Thu Aug 27 2026

High pressure is forecast to slowly move eastward from the eastern Dakotas this morning to Michigan by 00 UTC Saturday. This will bring quiet weather and overall pleasant conditions to the area through Friday. High temperatures today and Friday will range from 80 to 85 degrees with low temperatures on Friday morning ranging from the mid 50s to around 60. Aside from diurnally driven cumulus each day, clear skies are expected.

LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/

Issued at 1254 AM CDT Thu Aug 27 2026

Friday night and Saturday, upper ridge over the Central CONUS begins to break down and move eastward. Surface high pressure will have shifted to the east of the area Friday night resulting in south to southwesterly low level flow into the region, we will start to see temperatures and moisture gradually increase into Saturday. Precipitation chances have been trending upwards for Saturday, as a wave slowly approaches late Friday night and meanders through the area on Saturday. Some guidance would indicate the potential for a decaying line of showers/storms in the morning, with the potential for redevelopment along any outflow that afternoon. Although, much uncertainty exists owing to plenty of dry air for this to battle and a recent trend in the models to push the terminus of the low level jet northward into southeast Minnesota and Wisconsin. This will be something that we keep an eye on over the coming days. Will stick with the NBM PoPs at this point, where it highlights areas largely north of Interstate 80 in 20-40% chances.

Saturday night onward, ridging aloft shifts to the eastward with better return flow into the area. There are some differences between the models in the strength and placement of the ridge late this weekend into early next week. Model spread on forecast high temperatures next week varies from 6 to 8 degrees on Monday to as much as 10 degrees on Wednesday and Thursday so there is some variability in forecasts with some models showing forecast high temperatures in the mid to upper 90s. Decided to limit high temperatures during this period to the upper 80s to lower 90s due to the model variability which is close to the NBM 50th percentile forecast. With increasing humidity as well, some areas may have heat indices approaching 100 especially for area in southeast Iowa, west central Illinois and far northeast Missouri.

The strengthening Plains low level jet will allow PoPs to continue overnight Saturday into Sunday, largely north of Interstate 80. Upper level flow will generally be zonal to southwesterly through the remainder of the forecast period, which may put us under the active storm path. Thus, if this pattern holds true, we could be heading into a potentially more active stretch of weather into next week with daily chances for showers and storms especially for areas north of a Fairfield to Galesburg line. Global models are in general agreement on chances for precipitation, with some differences in the timing and track of these shortwaves. Although, the NBM introduces daily PoPs (20-40%) Sunday through Thursday. Given the uncertainties in the forecast it is too early to determine any severe threat.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1203 PM CDT Thu Aug 27 2026

VFR conditions to prevail through 08z.28 at all terminals. Surface high to slide overhead overnight tonight leading to clear skies, calm winds, and ideal radiational fog development. MVFR/IFR fog will be possible prior to sunrise, especially along and south of I-80 where dewpoint depressions will be lowest. Some guidance was hinting at some LIFR vsbys at BRL but have left out mention for now due to lower confidence. Any fog to lift/burn off just after sunrise.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.